All publications herein are incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. The following description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
Cytolethal distending toxin (CDT) is a bacterial protein toxin produced by several pathogenic bacteria. CDT is composed of three subunits, CdtA, CdtB and CdtC, which together form a ternary complex. CdtB is the active component, and CdtA and CdtC are involved in delivering CdtB into the cells. CDT controls host cells by CdtB-mediated limited DNA damage of the host cell chromosome, which triggers the response of the cell cycle checkpoint and results in G2 arrest in the cells. CDT also induces apoptotic cell death of lymphocytes, which may be relevant to onset or persistence of chronic infection by the producing bacteria. (Ohara et al., J. Biochem, 2004, Vol. 136, No. 4 409-413.) Additionally, the presence of CdtB is universal among bacteria that cause food poisoning (e.g., Campylobacter (e.g., C. jejuni, C. coli), Escherichia coli (e.g., enterotoxigenic E. coli (ETEC), enterohaemorrhagic E. coli (EHEC), enteropathogenic E. coli (EPEC)), Salmonella, Shigella, and Clostridium difficile).
Irritable bowel syndrome (“IBS”) is a disorder characterized by, inter alia, cramping, abdominal pain, bloating, constipation, and diarrhea. IBS can cause a great deal of discomfort and distress. While many people can control their symptoms with diet, stress management, and medications, for some people IBS can be disabling. They may be unable to work, attend social events, or even travel short distances. As many as 20% of the adult population have symptoms of IBS; making it one of the most common disorders diagnosed by doctors.
In addition to irritable bowel syndrome, another phenomenon linked to IBS is non-ulcer dyspepsia (NUD). This is a condition whereby subjects experience discomfort in the upper abdominal area that cannot be explained by findings on an endoscopy such as an ulcer or irritation of the lining of stomach or intestine. This condition is another of the functional bowel conditions. There is a general recognition that very often there is an overlap between IBS and NUD to a degree that is more than just common occurrence (Talley et al., The association between non-ulcer dyspepsia and other gastrointestinal disorders. SCANS J GASTROENTEROL 1985; 20:896-900). In addition, recent evidence suggests that acute gastroenteritis can precipitate IBS and NUD (Mearin et al., Dyspepsia and irritable bowel syndrome after a Salmonella and gastroenteritis outbreak: One year follow up cohort study. GASTROENTEROL 2005; 129:98-104.). This evidence suggests that the pathophysiology of IBS and NUD may be linked to this initial food poisoning insult. As such, it is likely that the same mechanisms are in play.
Accordingly, there exists a need for diagnosis, treatment, prevention and reduction of the likelihood of having or developing IBS as well as NUD. Heretofore, there has been no association between CDT and IBS or CDT and NUD. Based upon the inventors' findings, therapies and diagnostics based on the association between CDT and IBS as described herein can be beneficial for IBS subjects, to prevent or reduce a subject's likelihood of developing IBS and/or NUD.